With the development of the electronic technology, display devices, such as televisions, mobile phones, computers and personal digital assistants, have been widely used in various fields and electronic products and have been an indispensable part for people's life and work. An conventional display device includes a gate driving circuit which is mainly used to scan multiple stages of gate lines to scan pixel arrays electrically connected to the gate lines and then to display a picture in coordination with other line structures. For diverse demands on a gate driving circuit, designing of the gate driving circuit has become one of main research trends for developers nowadays.